linux-image-4.4.0-62-generic breaks Lenovo T440s on Ultradock

[Martin D. Weinberg]

When using with dock, attached monitor is not detected, laptop monitor remains blank. Requires a reboot

4.4.0-59 works fine. I'm guessing this is due to the i915 patches for DP.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: linux-image-4.4.0-62-generic 4.4.0-62.83
ProcVersionSignature: Ubuntu 4.4.0-59.80-generic 4.4.35
Uname: Linux 4.4.0-59-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.5
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC3: weinberg 2945 F.... pulseaudio
 /dev/snd/controlC2: weinberg 2945 F.... pulseaudio
 /dev/snd/controlC0: weinberg 2945 F.... pulseaudio
 /dev/snd/controlC1: weinberg 2945 F.... pulseaudio
CurrentDesktop: Unity
Date: Mon Feb 6 20:15:05 2017
EcryptfsInUse: Yes
HibernationDevice: RESUME=UUID=b572432a-a870-4698-af05-eb9ac5b5dfb5
InstallationDate: Installed on 2016-05-06 (276 days ago)
InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1)
MachineType: LENOVO 20ARA0S100
ProcEnviron:
 LANGUAGE=en_US
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-59-generic root=UUID=0a196d38-a419-4a42-b659-7108068e6ce5 ro quiet splash vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-4.4.0-59-generic N/A
 linux-backports-modules-4.4.0-59-generic N/A
 linux-firmware 1.157.6
SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 03/19/2014
dmi.bios.vendor: LENOVO
dmi.bios.version: GJET74WW (2.24 )
dmi.board.asset.tag: Not Available
dmi.board.name: 20ARA0S100
dmi.board.vendor: LENOVO
dmi.board.version: Not Defined
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: Not Available
dmi.modalias: dmi:bvnLENOVO:bvrGJET74WW(2.24):bd03/19/2014:svnLENOVO:pn20ARA0S100:pvrThinkPadT440s:rvnLENOVO:rn20ARA0S100:rvrNotDefined:cvnLENOVO:ct10:cvrNotAvailable:
dmi.product.name: 20ARA0S100
dmi.product.version: ThinkPad T440s
dmi.sys.vendor: LENOVO

[Brad Figg (brad-figg)]

This change was made by a bot.

[Martin D. Weinberg (martin-weinberg-5)]

Also, and not sure if this is related, Plymouth does not correctly render the splashscreen on boot up. Part way through, the screen blanks and only the "dot icons" are visible. Again, this does not occur for earlier kernels.

[Martin D. Weinberg (martin-weinberg-5)]

Another thought: I'm using the modesetting driver, not the intel driver.

[Joseph Salisbury (jsalisbury)]

Would it be possible for you to test this latest kernel and post back if it resolves this bug?
See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed.

Thank you in advance!

[Joseph Salisbury (jsalisbury)]

If -proposed still has the bug, we can peform a kernel bisect to identify the commit(s) that introduced this bug.

[Martin D. Weinberg (martin-weinberg-5)]

I am happy to report that linux-image-4.4.0-63-generic from xenial-proposed _is_ working correctly with the T440s on and off the dock. So the bug is gone from the -proposed kernel package.

Thanks for that!

If we could only get the DP audio to work on the dock, sigh. It hasn't worked since Kernel 3.19 or thereabouts.